Toyora, Dactylioceras helianthoides zone, Locality Nishinikayama 20 (Jurassic of Japan)

Where: Yamaguchi, Japan (34.3° N, 131.0° E: paleocoordinates 44.9° N, 138.7° E)

• coordinate estimated from map

• small collection-level geographic resolution

When: Nb Member (Nishinakayama Formation), Early/Lower Toarcian (183.0 - 182.0 Ma)

• Locality belongs to the Dactylioceras helanthoides zone. The Nishinakayama Fm attains about 300m in maximum thickness, and is lithostratigraphically subdivided into three members, namely Na, Nb (black shales with intercalations of fine sandstone; 160m thick), and Nc in upward sequence.

• bed-level stratigraphic resolution

Environment/lithology: marine; black shale

• Lower to Middle Jurassic shallow marine (partly brackish?) clastic deposits

Size class: macrofossils

Primary reference: K. Tanabe. 1991. Early Jurrasic Macrofauna of the Oxygen-Depleted Epicontinental Marin Basin in the Toyora Area, West Japan. Saito Ho-on Kai Special Publication 3:147-161 [M. Aberhan/S. Nurnberg/P. Wagner]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 38224: authorized by Martin Aberhan, entered by Sabine Nürnberg on 19.04.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Bivalvia
 Ostreida - Posidoniidae
Bositra sp.
Bositra sp. De Gregorio 1886 oyster
sp. B